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3964_00 Datasheet, PDF (1/10 Pages) Allegro MicroSystems – DUAL FULL-BRIDGE PWM MOTOR DRIVER
3964
DUAL FULL-BRIDGE PWM MOTOR DRIVER
A3964SLB
OUT 1B 1
SENSE 1 2
OUT 1A 3
LOAD 4
SUPPLY
GROUND 5
1
VBB
GROUND 6
VREF(IN) 7
RC 1 89
PHASE 1 9 1
ENABLE 1 10
20 OUT 2B
2
19 SENSE 2
18 OUT 2A
V CC
17
LOGIC
SUPPLY
16 GROUND
15 GROUND
14 V REF(OUT)
13 RC 2
2 12 PHASE 2
11 ENABLE 2
Dwg. PP-047-1
ABSOLUTE MAXIMUM RATINGS
Load Supply Voltage, VBB . . . . . . . . . 33 V
Output Current, IOUT (10 µs) . . . . . . ±1.0 A*
(continuous) . . . . . . . . . . . . . ±800 mA*
Logic Supply Voltage, VCC . . . . . . . . . 7.0 V
Logic Input Voltage Range,
VIN . . . . . . . . . . . -0.3 V to VCC + 0.3 V
Sense Voltage, VS . . . . . . . . . . . . . . . 1.0 V
Reference Output Current,
IREF(OUT) . . . . . . . . . . . . . . . . . . 1.0 mA
Package Power Dissipation,
PD . . . . . . . . . . . . . . . . . . . . See Graph
Operating Temperature Range,
TA . . . . . . . . . . . . . . . . -20°C to +85°C
Junction Temperature, TJ . . . . . . +150½°†
Storage Temperature Range,
TS . . . . . . . . . . . . . . . -55°C to +150°C
* Output current rating may be limited by duty cycle,
ambient temperature, and heat sinking. Under any set
of conditions, do not exceed the specified current rating
or a junction temperature of 150°C.
† Fault conditions that produce excessive junction
temperature will activate the device’s thermal shutdown
circuitry. These conditions can be tolerated but should
be avoided.
Designed for pulse-width modulated (PWM) current control of bipolar
stepper motors, the A3964SB and A3964SLB are capable of continuous
output currents to ±800 mA and operating voltages to 30 V. Internal fixed
off-time PWM current-control circuitry can be used to regulate the maximum
load current to a desired value. An internal precision voltage reference is
provided to improve motor peak-current control accuracy. The peak load
current limit is set by the user’s selection of an external resistor divider and
current-sensing resistors.
The fixed off-time pulse duration is set by user-selected external RC
timing networks. The capacitor in the RC timing network also determines a
user-selectable blanking window that prevents false triggering of the PWM
current control circuitry during switching transitions. This eliminates the need
for two external RC filter networks on the current-sensing comparator inputs.
For each bridge the PHASE input controls load current polarity by
selecting the appropriate source and sink driver pair. For each bridge the
ENABLE input, when held high, disables the output drivers. Special power-
up sequencing is not required. Internal circuit protection includes thermal
shutdown with hysteresis, transient-suppression diodes, and crossover-current
protection.
The A3964SB is supplied in a 24-pin plastic DIP with copper heat sink
tabs; A3964SLB is supplied in a 20-lead plastic SOIC with copper heat sink
tabs, and is available in a lead (Pb) free version with 100% matte tin
leadframe plating. The power tabs are at ground potential and need no
electrical isolation.
FEATURES
■ ±800 mA Continuous Output Current Rating
■ 30 V Output Voltage Rating
■ Internal PWM Current Control, Saturated Sink Drivers
■ Internally Generated, Precision 2.5 V Reference
■ Internal Transient-Suppression Diodes
■ Internal Thermal-Shutdown Circuitry
■ Crossover-Current Protection, UVLO Protection
Part Number Pb-free* Package
Packing
A3964SLB-T
Yes 20-Lead SOIC 37 per tube
A3964SLBTR-T Yes 20-Lead SOIC 1000 per reel
*Pb-based variants are being phased out of the product line. The variants cited in this
footnote are in production but have been determined to be LAST TIME BUY. This
classification indicates that sale of this device is currently restricted to existing
customer applications. The variants should not be purchased for new design
applications because obsolescence in the near future is probable. Samples are no
longer available. Status change: October 31, 2006. Deadline for receipt fo LAST TIME
BUY orders: April 27, 2007. These variants include: A3964SB, A3964SLB, and
A3964SLBTR.